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Title: The determining factor on MH/s? Post by: grue on March 12, 2011, 05:54:24 PM What's the most important factor that determines a card's hashing ability? From what i heard, it's based on the amount of shaders. is that correct? what about core clock?
Title: Re: The determining factor on MH/s? Post by: Dude65535 on March 12, 2011, 06:01:39 PM shaders, clock speed and chip design are the determining factors
Title: Re: The determining factor on MH/s? Post by: Cryptoman on March 12, 2011, 06:06:28 PM On a related note, does anyone know how many integer operations are necessary to compute one hash?
Title: Re: The determining factor on MH/s? Post by: os008 on March 12, 2011, 06:44:37 PM Interesting question. I made a quick calculation ...
5850 -> 300 MH/s -> 2.5 TFLOPs 2,500,000,000 / 300,000,000 = 8.33 OPs I'd say 9 OPs. Someone here who has more expertise in this, please provide some feedback. Title: Re: The determining factor on MH/s? Post by: Beremat on March 12, 2011, 06:52:43 PM Interesting question. I made a quick calculation ... 4850 -> 75MH/s -> 1TFLOP5850 -> 300 MH/s -> 2.5 TFLOPs 2,500,000,000 / 300,000,000 = 8.33 OPs I'd say 9 OPs. Someone here who has more expertise in this, please provide some feedback. 1,000,000,000 / 75,000,000 = 13.333 It's probably dependent on core architecture as well. Title: Re: The determining factor on MH/s? Post by: Meni Rosenfeld on March 12, 2011, 07:11:22 PM FLOPs are floating point operations per second, so I don't think they're what we're supposed to look at.
Title: Re: The determining factor on MH/s? Post by: ArtForz on March 12, 2011, 07:13:47 PM off-by-3-orders-of-magnitude.
HD5xxx needs about 4150 integer operations per hash HD4xxx and nvidia 2/4/5xx about 6350 integer operations. for all current architectures integer ops/second = number of shader ALUs * clock. so a 5870 at 1600 ALUs * 850MHz = 1360000M intops/second, / 4150 = ~ 327.7Mh/s 4870: 800 * 750M / 6350 = ~ 94.5 Mh/s GTX580: 512 * 1544M / 6350 = ~ 124.5Mh/s etc... usually published FLOPS numbers are simply intops * 2 (one muladd counts as 2 operations). Title: Re: The determining factor on MH/s? Post by: os008 on March 12, 2011, 07:29:54 PM HD5xxx needs about 4150 integer operations per hash Thank you for the explanation.Quote usually published FLOPS numbers are simply intops * 2 (one muladd counts as 2 operations). Wouldn't that mean ATi is much superior to nVidia in FLOPs; contrary to the reality? Don't you mean FLOPs = INTOPs / 2 ?Title: Re: The determining factor on MH/s? Post by: Garrett Burgwardt on March 12, 2011, 07:38:04 PM FLOPS are completely irrelevant, since the hashing algorithm uses fixed point calculations.
You could not be more wrong by looking at the FLOPS rating of a card. Title: Re: The determining factor on MH/s? Post by: os008 on March 12, 2011, 08:14:36 PM There is still a correlation between FLOPS and Integer operations. That's what i would like to know; what's the equation to convert between them?Title: Re: The determining factor on MH/s? Post by: ArtForz on March 12, 2011, 08:27:49 PM published FLOPS for GTX580: 1581.1G
512 ALUs * 1544 MHz shader clock * 2 (muladd factor) = 1581.056G published FLOPS for HD5970: 4640G 3200 ALUs * 725MHz * 2 (muladd factor) = 4640G hey, what a coincidence! Title: Re: The determining factor on MH/s? Post by: gigabytecoin on March 12, 2011, 08:57:13 PM FLOPS are completely irrelevant, since the hashing algorithm uses fixed point calculations. You could not be more wrong by looking at the FLOPS rating of a card. Ok, so where are the FPOPS ratings?! :P Title: Re: The determining factor on MH/s? Post by: os008 on March 12, 2011, 09:10:16 PM hey, what a coincidence! So to finish an integer operation, it needs TWO sub-operations? I would've thought floats were harder.Ok, so where are the FPOPS ratings?! :P http://pastebin.com/AvymGnMJhttp://en.wikipedia.org/wiki/Comparison_of_ATI_Graphics_Processing_Units#PCIe_.28HD_5xxx.29 Title: Re: The determining factor on MH/s? Post by: apofis on March 12, 2011, 09:11:36 PM Look here http://forum.boinc.ru/yaf_postst395_Spicok-vidieokart-dlia-kranchingha-v--MilkyWay-home.aspx
Title: Re: The determining factor on MH/s? Post by: grue on March 14, 2011, 03:03:10 PM thanks for all the input guys.
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